Fig. 3.

Direct binding of RACK1 to FlnA. FlnA was immunoprecipitated from Calu-3 cells, immobilized on PVDF paper in a slot-blot filter apparatus, and overlaid with recombinant (untagged) RACK1. The membrane was probed with anti-RACK1 and anti-FlnA antibodies. A: representative binding experiment showing that RACK1 binds to immobilized FlnA in a concentration-dependent manner. B: means ± SE values from 5 experiments showing concentration-dependence of RACK1 binding to FlnA. Binding was quantitated as the intensity ratio of RACK1 to FlnA as measured by densitometry. Results of ANOVA (P = 0.0086) and Student-Newman-Keuls Multiple Comparison posttest: *P < 0.05 for 1 vs. 4 μl RACK1; **P < 0.01 for 1 vs. 8 μl RACK1.